Locomotive draft appliance



May 26, 1925.

1,539,124 D. M. LEWIS LOCOMO'I-IVE DRAFT APPLIANCE Filed Aug. 18 1921 5 Sheets-Sheet 1 l I l A um a y@ May 26, 1925.

D. M. LEWIS LOCOMOTIVE DRAFT APPLIANCE May 26,1925. V1,539,124

- D. M. LEWIS LOCOMOTIVE DRAFT APPLIANCE Filed Aug. 18, 1921 s sheets-sheet s 551g@ @Haine/13M May 26, 1925.

Si TAT E S l 'DAVID II. LnwIs, or cnicnco, ILLINOIS, AssIeNon fro Lnwrs- DRAFT 'UNITEQ asian/i APrLLaNo'n COMPANY, A CORPQRATION OF ILLINOIS.

LocoMo'rIvn naam: APPLIANCE. i

Application filed'August 18, 1921. Serial 1101.493311.

To all who/172; 'it may concern.' f

. Be it known that I, `DAVID M. Lnwis,`a

citizen of the United States, residing at Chi-- cago, inthe county of Cook and State of` Illinois, have invented certain new and use` ful Improvements in Locomotive Draft Appliances, of which the following is awspeci-v iCatIOn.

This. inventionv relates to locomotive draft appliances, and it has for one of its primary objects the provision of an improved arrangement whereby approximately con tinuous draft is obtained in contra'distinction to the intermittent or pulsating draft of standard practice. i l

. Another object of my invention is to provide an improved draft appliance of the characteristics noted in which obstruct-ion of the smoke box is reduced to a minimum. l

Still another object of the invention isto provide an improved draft appliance such that the front end is substantially selfcleaning, and inwhich an improve-d and effective arrangement. of netting may. be elmployed. f f p My invention also contemplates an improved arrangement of parts whereby the effectiveness of the draft is increased; and

an improved arrangement and combination of stack, petticoat and nozzle.

The foregoing, together with such other objects as may ,hereinafter appear, I obtain by means of a construction which I have illustrated in preferred form in the accompanying drawings, wherein:

Fig. 1 is a side elevation andpartial sec! 10 is a damper governing the'flow of the products of combustion from the flues into the smokebox beneath the diaphragm 9. Extending forwardly of the diaphragm, preferably to the front wallof thefsmoke box, is a table plate 11 which surrounds the nozzle A, the construction of which will be hereinafter described. As will be seen in Fig. 2 the tablell extends onlyk part Vway across'the smokebox and it has secured to its Vside edges downwardly inclined refiector` plates 12, which preferably extend to the sides of the smoke box shell with an intermediate portion opposite theV main nozzle casting a cut out providing openings or passages, 13 for the passagey ofthe products of combustion at the sides of the smoke box.

The nozzle A preferably consists ofthe single piece main casting a, round at Vthe bottom and flanged for bolting tothe saddle casting, but Haring upwardly and outwardly from said round portion in a direction longitudinal of thesmoke box and narrowing inf a transverse direction and terminating in an elongated housing portion a', the major axis of which is larranged longitudinally 4of the smoke box. The nozzle opening is adapt-` ed to be formed by the two vanes 14, geared together` soas to move in unison and hav ing shafts 15, suitably mounted inthehous-` ing a. One of said shafts has an extension 15 extending forwardly through the front' wall of the box, and provided with a weightedv larm 16, which normally tends to hold the vanes in closed position, as indicated in Fig.:` 2. The arm 16 is also connected to a dash pot mechanism 17, adapted to cushiony its movements. These vanes extend longitudr nally ofthe nozzle casting and when they open they create a long narrow nozzle 'opening which also extends `longitudinally of` the smoke box.V f; .y i The stack, 18, of the smoke box is pref! erably round invcro'ss section and its petticoat 19 is also round at the top but narrowsv toward the bottom ina direction 'transverse the smoke box land elongated in a. direction longitudinal of the smoke box, to corre-4 spond with the shape anddisposition of the nozzle. The bottom` of the petticoat is flared laterally and longitudinally of the smoke. box. f' Y `.The saddle casting is preferably of the outsideexhaust and inside admission type,

each valve chest19 having exhaust cavities 20and 21and a livesteam cavity22. The exhaustpassages 20a and 21a leading fromv the exhaust cavities merge in the-'usual manner and deliver the exhaust steam, to` the nozzle.A The valve chest `bushings are shown open and have secured over such open ends elbow fittings 25 connected to opposite ends, respectively, of a volume. chamber or receiver 26, located in front of the saddle casting and extending transversely thereof. The valves 27 are of the hollow piston type.

It will be seen that by the arrangement vjust described the volume chamber is connected at either end to the respective forward end of each valve chest so that the volume chamber or receiver may be said to be connected in parallel with the exhaust through the nozzle; The volume chamber is made of ample capacity to act as a reservoir for a relatively large quantity of'steam.

lilith the yparts in the' position shown in Fig. 3, it willl be seen that the cylinder at the left is receiving live pressure in the back through the port 24, and: the front endl of cylinder is exhausting through the port 24', to the exhaust cavity 2l of the chest from whence it flows to exhaust passage 211 land also to the receiver 26 throughjelbow 25. Exhaust steam may also iiow through the hollow piston valve QT to the exhaust cavity 2O of the right hand valve chest and thence to exhaust passage 20w.

`In the cylinder' and valve chest atthe right of Fig. 3, exhaust is occurring from the' back end of the cylinder through' the port 24 at the same time as from'the front end of tlie other cylinder, and this exhaust steam may flow through the exhaust cavity 2@ and passage 2Oa at the right or through the valve in af direction the reverse of that throught'he valve at the left.r Thus, it will' be seen that exhaust steam is bound to flow into the volume chamber' until pressure equilibrium is` established?. A

in the event-that the valve at the right of' Fig. 3 covers the port in the rear bushing, then the exhaust steam in the volume Achamber, will flow through both exhaust pas sages on that side of the saddle casting. In the event that all ofthe exhaust ports in the forward valve chest bushings are closed, then the exhaust steam from the 'volume chamber is f'ree Vto flow through all four exhaust saddle Vpassages to the exhaust stand base cavities.k y n l The operation Vis as iol'lows-*Wheir ex-A haust takes place from the cylinders, the exhaust steam divides, a.I portion finding its way directly to the nozzle through the exhaust passages and the remainder going to the volume chamber, the pressure'of' the exhaust steanibeing lowered by virtue of the expansion which takes place. The steam which is inI the volume chamber' backs up 5 Y the steam passing directly'to` the nozzle and isl free; to flow, particularly in the interval'y between exhausts -fronr the cylinders, to the nozzlest so'- that there` ispractically, a continuous flow of steam from the nozzle at 'all times when the engine 4is using steam.y ln

fact the pulsations except at low speed, are substantially ironed out so that at the higher speeds the blast issuing from the nozzle is not only continuous but practically constant slightly less pressure. If for any reason the pressure obtaining' in the exhaust passages and receiver should tend to increase,'the vanes will openy more widely against the action of their weights, thus increasing the area of nozzle opening and automatically lowering the pressure, while if the pres# sure tends to decrease, the vanes will more toward each other, reducing the size of the nozzle' opening, automaticallybringingbaclr the pressure tol the preselected value; governor mechanism is thus actuated by the exhaust pressure conditions obtaining in the exhaust passages and in the receiver, on the exhaust side of the cylinders. The pres sure to which the weights of the vanes should be adjusted depends upon the type of enginey and the class of service, but it is preferably to so weight the vanes as to maintain a vpressure which is just sufficient to maintain proper draft throughout the range of working speeds. Because ofthe continuous character of the' blast and because of the fact that the blast column is elongated in cross section and thus secures a maximum entrainm'ent area, I have found by experiencelthat adequate draft can be maintained with a back pressure greatly lower than that which obtains in standard practice.

In so far as the draft created is concerned, it will be observed that the arrangement of the diaphragm', table plate and detlector plates in combination kwith the peculiarly shaped nozzle, is such tl'iat 'the flow of the products of combustion from the flues is for the most part downward beneath and past rthe diaphragm, under the table plate and then laterally outward toward the sides through the passages 13, and then inwardlyv toward the exhaust blast. rThe diaphragm 9, of course,- extends entirely across the width of the smoke box while the table l-l. does not and at the extreme lower outer edges or corners of the diaphragm there is a small area between such edges a-nd the deflectorV plates 12 through which the hot gases,a-fter passing under the diaphragm, are drawnv into the petticoat without passing beneaththe table platey or under the deflector plates.' Thus, notwithstanding the. i ef that the exhaust blast is in the form of a relatively thin, wide sheet, the major axis of which is longitudinal of the Vsmoke box, the flue section is approximately uniformly subjected to draft so that the `center flues are not overworked in comparison to the side fiues,fand neither is there toovmuch draft. at the side flues Vwhich is also to be yavoided and is incident to some yforms of prior practice. p

In addition to the obtaining of adequate draft at all operating speeds, by my im` provements I also have found that no sparks are thrown because of the lower velocity of the blast and the fine particles which are drawn. through the flues from theire `box are scoured out from the smoke box, and carried out in suspension by reason of the fact thatl all gas flow thereinLV is kclose to the sides and bottom of thesmoke box. The smoke box is thus very effectively self-clean mg.

lith respectto the netting, thev arrange ment is such that only two longitudinally extending sheets 27 need be employed These sheets are secured to the table plate at the unction with the deflector plates and extend upwardly and outwardly to the sides of the box so that all the gases must pass therethrough.V This is a simple arrangement which tends, along with other' features of construction, 4to render the ysmoke box relatively unobstructed.

The combination of the round stack with a petticoat or extension and the nozzles of the sha-pes described is also very effective for the reason that the shape of the parts tirst securesV maximum entrainmentby virtue of creating an elongated blastcolumn of maximum entrainment area and then secures a complete filling of the stack by changing the blast and gas column into a round column which results in maximum efficiency of the blast in the creation and maintenance of draft. .Y

I claim:

l. In a locomotive draft appliance the combination of a cylinder, an exhaust passage, a nozzle, anda receiver in parallel with the exhaust passage.

2. In a locomotive draft appliancethe combination of a pair of cylinders, a nozzle, exhaust passages leading from the cylinders to the nozzle, and a receiver connected so as to be in parallel with the exhaust passages.

3. In aI locomotive `draftappliance, the combination of a pair of cylinders having chests with outside. exhaust passages and inside admission, a nozzle, a receiver, and a connection between the receiver and each chest 'establishing communication between the receiver and the exhaust cavities of the chests. Y

4. In a locomotive `draft appliance, .the

. combination of asaddle casting having a pair of cylinders, a pair of valve chests, and outside exhaust passages andv mslde admis` sion,`a transversely extending receiver ad-VV` jacent the saddle, and, a-nelbow rconnecting. each end of the receiver to the exhaust cavity of a chest. Y ,Y t

5. In a locomotive draft appliance, the combination of a saddle casting having a pair ofcylinders, a pair of valve chests, `and outside exhaust passages and inside :admis-A sion, a hollow valve ineach chest, a re `ceiver, and a connection Vbetween the receiver and the exhaust cavities of thechests. T6. In a locomotive ydraft appliance the combination of ka cylinder, an:4 exhaust pas# sage, a nozzle, and a Vreceiver in parallel with theexhaust passage, said nozzle hav-l ing automatic-ineans creating thenozzle opening responsive to the 'exhaust` pressure conditions. i 7 f L 7. In alocomotive draftappliance the combination of a cylinder, an exhaust passage, a nozzle, and al receiver in parallel with the exhaust passage, said nozzle `having an automatic governor means responsive to the y exhaust` pressure conditions.

8, In a locomotive draft appliancethe combination of a cylinder,-an exhaust passage, ainozzle, and areceiver in parallel with the exhaust passage, said nozzle being" elongated.- n r n.

9. Iny a locomotive 'draft appliance the combination of a cylinder, `an exhaust pasa. sage, la nozzle, anda receiver in parallel. with the -exhaust passage, said nozzle being elonf` gated with its major axis extending longi-` tudinallyof the smoke box.

"101 In a locomotive draft appliance the@ combination of a cylinder, an exhaust `pasV sage, a nozzle, and a receiver in parallel with the exhaust passage, said nozzle being elongated with its major axis extending longitudinally of the smoke box, together with a stack and an apron of corresponding cross section.` l. of

lL'In a locomotive draft appliance the combination, of a l cylinder, an exhaust passage, a nozzle,.and a receiver in parallelwith the exhaust passage, said nozzle being elon-` gated with its ina-jor axis extending longitudinally of the smoke box, together-,with a j round stack and an apron therefor, the lower portion of which is elongated in cross section in accordance with the nozzle.

l2. In a locomotive, the combination of a flue sheet, a cylindrical smoke box, an elongated nozzle with its major axis longitudinal of the box, a'diaphragmy intermediate the nozzle and flue sheet, and a table plate-` surrounding the nozzle and extending longitudinally of the boxfrom the diaphragm forwardly and having its side edges termii nating short of the sides of the smoke box,

- nozzle and tine sheet, and a table plate surrounding the` nozzle and extending longitudinally ofthe box from the diaphragm forwardly and having its side edges terminating short vof the sides of the smoke box,-together with dei'lector plates angling fromthe side edges ot the table plate and netting arranged longitudinally of the smoke boxextending from the intersections of the table plate and deiiector plates upwardly to the sides of the smo-ke box.

l 14. In a locomotive, the combination of a flue sheet, `a cylindrical smoke box, an elongated nozzle with its major axis longitudinal of the box, a'diaphragin intermediate the nozzle and flue sheet, and a tableplate surrounding the nozzle and extending longitudinally of the box from the diaphragm forwardly and having its side edges termi- .uating short of the sides of tliesmokefbox,

together with'de-flector plates angling from the side edges of the table plate andvnetting arranged longitudinally of `the smoke box extending from the intersections of the table and delector plates upwardly and .outwardly to the sides of the smoke box.

15. In a locomotive, the combination o-a flue sheet, a cylindrical smoke box, anelon-V gated nozzle with its major axis longitudinal of the box, a diaphragm intermediate' the nozzle and flue sheet, and a .table plate surrounding the nozzle and extending longitudinally-of the box from the diaphragm forwardly and `having its side edges terminating short ot the sides of the smoke box, together with netting extending upwardly from the side portions of the table plate to the sides of the smoke box and longitudinally thereof. v K

i 16. In a locomotive, the combination of a flue sheet, a cylindrical smoke box, an elongated nozzle with its major axis longitudinal of the box, a diaphragm intermediate the:

nozzle and flue sheet, and a table plate surrounding the, nozzle and extending. longitudinally of the box from the diaphragm forwardly and having its side edges termi-- nating short of the sides of the smoke box,

together with deflector plates angling 'from the side edges of the table plate and providing passages for gas iow at the sides of the smoke box. p l

17. In a locomotive, the combination of a flue sheet, a cylindrical smoke box, an elongated nozzle with its major axis longitudr nal of the box, a diaphragm intermediate the nozzle andiuesheet, and a table plate.

surrounding tlienozzle and extending longitudinally ofthe box'from the diaphragm forwardly and having, its side kedges terminating short oi the sides of the smokebox,

combination of an elongated nozzle, a sub-. stantially round stack, and a petticoat forl the* stack the lower portion otwhicli hasta cross section corresponding' vto that of the nozzle together with means `prodi-icing a sub- .Y

stantially continuous blast from the nozzle.

20. Inra locomotive draft appliance the combination otra cylinder, a nozzleadapted to receive exhaust steam directly from tlic cylinder for creating draft blast and a receiver also open to the exhaust from the cylinder and adapted to deliver exhaust steam to thenozzle.

In testimony whereof, I have hereunto signed my name. v

DaviD M. Lewis.

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